Retired

     

Description

The BLT is a simple Z-Match tuner that works from 10-40 meters, designed by Charlie Lofgren for NorCal.  Charlie is probably the number one man in the world when it comes to Z-Match Tuners, and he has designed this one especially for NorCal.  The tuner tunes balanced feedlines, thus the name "BLT" for Balanced Line Tuner for the mnemonically-challenged among us. Charlie originally designed the tuner to go with the SMK-1 and the NorCal Doublet for 40 meters, but when he delivered his design we found it tuned other bands also. With the NorCal Doublet, it tunes 10 - 40 meters. We rate the tuner at 5 Watts, but it will probably be safe at 10 W. It comes with the Dan Tayloe N7VE LED SWR indicator built in, and is an absorptive bridge, so you won't fry the finals as you tune. Great design, by a great designer. All parts for the tuner are included, including the case. It uses polyvaricon caps. There is already a mod to convert it to end-fed wire and coax. All you have to do is add one BNC and a SPDT switch, and you can use end fed wires and coax antennas. The connectors included are two 5-Way Binding Posts for the balanced feedline, and a BNC to connect to your rig.


Download the "BLT Tuner Construction Manual" (with active hyperlinks!)  -- 1 MB


Custom Enclosue & PCB

We used to supply some copper-clad material for a case and a clear plastic top half for the BLT Tuner Kits. But after several years of producing the kit, I have run out of the clear plastic covers, so I decided to investigate the possibility of using an aluminum case. I checked with Ten-Tec, even ordered some of their TP-15 cases to try out. I wanted to make sure that the tuner would still work okay - and it does! Walter Dufrain, AG5P built a tuner using this metal enclosure approach, did some extensive testing, and reports that all is fine. Well, I thought that I could get a custom case made and it would be predrilled, which the Ten-Tec case would not have been. Several guys have told me that the hard part of building up the BLT was the case, and that they wished it would come in a case of its own. I thought about that, and decided to see what I could get done.

So I went to San Jose and contacted several sheet metal places and finally found one that would do the job ... The BLT is now packaged in a .062 aluminum case, clam shell style, front and back panels predrilled, and will be held together with counter sunk flat head screws and PEM nuts.  The size is 3" x 3" x 1 5/8".  Front and back panels are 1.5". Think of the case for the SST and you'll get the idea.

I also decided that we need a pc board to replace the Manhattan style construction used in the old tuner. We now supply a Pittsburg Style Board . Pittsburg style means that the pads and traces are etched on the board. All that you have to do is put the parts on the board and solder. The layout is already there, and no pads to glue down.


Review

"Got mine finished last night and never have I had a kit that I put together work the first time. The BLT tuner worked great. Just had the diode in backwards but that was easy to fix. Doug has made one of the best manuals for a kit that I have seen. Photos are great and sure help you keep on track. This kit would be great for the first time builder. It was great to see the LED go out on 40 meters. Doug you have set the standards for a user manual. A big thanks!"
 ...  72 Gene N0MQ



Panel Labels


NorCal BLT Tuner .... with new aluminum case (shown on left)
(Inside of Tuner shown on right with older-style case)



Jerry Haigwood, W5JH created these PANEL LABELS that can be attached using 2" clear box tape.
He uses an Exacto knife to cut out the holes for the components. Components also help hold the overlays on the panels. The overlays will give the BLT a finished professional look!
(Download a PDF file containing actual size color overlays)

 

Ordering the BLT


This kit can be orderded through Doug Hendricks QRP Kits


Page last updated: 03/11/2019, 21:08:58
Page Maintained by: dean@alpinesoft.com
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